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991.
Prenatal alcohol exposure (PAE) and traumatic childhood experiences (trauma) such as abuse or neglect can each cause central nervous system neurobiological changes or structural damage which can manifest as cognitive and behavioural dysfunction. In cases where both exposures have occurred, the risk of neurodevelopmental impairment may be greater, but this interaction has not been well studied. Here we present a systematic review that identified five primary research studies which investigated either the impact of trauma in children with PAE, or of PAE in children with trauma. Due to the heterogeneity of studies, narrative analysis was applied. Children in these cohorts with both exposures were more likely to show deficits in language, attention, memory and intelligence, and exhibit more severe behavioural problems than children with one exposure in absence of the other. However, the current literature is scarce and methodologically flawed. Further studies are required that: assess dual exposure in other neurodevelopmental domains; feature developmentally impaired yet non-exposed controls; and account for the wide spectrum of effects and different diagnostic criteria associated with PAE. 相似文献
992.
993.
《Clinical and experimental hypertension (New York, N.Y. : 1993)》2013,35(4):613-624
Six consanguine monogamcus SHR couples (Gl) were treated from 5 weeks of age on with an alpha blocker, nicergoline, 0.1 mg/kg/day i.p. Male rats were treated without interruption; treatment was withheld in female rats from delivery to weaning. They were compared to six similar SHR couples who were only daily i.p. injected with the same volume of solvent in the same conditions as controls, as well as with naive (untreated) rats. Second (G2) and third (G3) generation rats (untreated) were studied. In Gl rats, systolic blood pressure (SBP), heart rate, heart weight/body weight ratio and bulbar noradrenaline content were decreased (compared to control or naive rats), while plasma renin activity (PRA) and hypothalamic noradrenaline content were not changed. In G2 rats, SBP and PRA were decreased, all other parameters being unchanged. No parameter was changed in G3 rats. This appears to be the first report of a preventive effect of antenatal treatment on the development of hypertension in SHR. 相似文献
994.
Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder and the leading cause of anovulatory infertility. Characterised by hyperandrogenism, menstrual dysfunction and polycystic ovaries, PCOS is a broad-spectrum disorder unlikely to stem from a single common origin. Although commonly considered an ovarian disease, the brain is now a prime suspect in both the ontogeny and pathology of PCOS. We discuss here the neuroendocrine impairments present in PCOS that implicate involvement of the brain and review evidence gained from pre-clinical models of the syndrome about the specific brain circuitry involved. In particular, we focus on the impact that developmental androgen excess and adult hyperandrogenemia have in programming and regulating brain circuits important in the central regulation of fertility. The studies discussed here provide compelling support for the importance of the brain in PCOS ontogeny and pathophysiology and highlight the need for a better understanding of the underlying mechanisms involved. 相似文献
995.
Emmanuel A. Audenaert P. J. De Roo P. Mahieu A. Cools N. Baelde K. D’Herde R. Verdonk 《Medical & biological engineering & computing》2009,47(5):557-563
Accurate prediction of muscle parameters can be used for customization of biomechanical models. A method is presented to estimate
the volume of triangular-shaped muscles from ultrasonographic measurements. The deltoid muscle was used to validate the technique
in a cadaver study of 12 shoulders. The relationship between isokinetic abduction strength and estimated deltoid muscle volume
of the dominant shoulder of 30 healthy male subjects was analysed. Isokinetic joint moments were quantified using the Biodex
System 3. A significant relationship (R = 0.87; p < 0.001) between the calculated deltoid volume and the isokinetic abduction peak torque was established. 相似文献
996.
ObjectivesTo investigate the correlation between the imaging features obtained by an automated breast volume scanner (ABVS) and molecular subtypes of breast cancer.MethodsWe examined 303 malignant breast tumours by ABVS for specific imaging features and by immunohistochemical analysis to determine the molecular subtype. ABVS imaging features, including retraction phenomenon, shape, margins, echogenicity, post-acoustic features, echogenic halo, and calcifications were analysed by univariate and multivariate logistic regression analyses to determine the significant predictive factors of the molecular subtypes.ResultsBy univariate logistic regression analysis, the predictive factors of the Luminal-A subtype (n = 128) were retraction phenomenon (odds ratio [OR] = 10.188), post-acoustic shadowing (OR = 5.112), and echogenic halo (OR = 3.263, P < 0.001). The predictive factors of the Human-epidermal-growth-factor-receptor-2-amplified subtype (n = 39) were calcifications (OR = 6.210), absence of retraction phenomenon (OR = 4.375), non-mass lesions (OR = 4.286, P < 0.001), absence of echogenic halo (OR = 3.851, P = 0.035), and post-acoustic enhancement (OR = 3.641, P = 0.008). The predictors for the Triple-Negative subtype (n = 47) were absence of retraction phenomenon (OR = 5.884), post-acoustic enhancement (OR = 5.255, P < 0.001), absence of echogenic halo (OR = 4.138, P = 0.002), and absence of calcifications (OR = 3.363, P = 0.001). Predictors for the Luminal-B subtype (n = 89) had a relatively lower association (OR ≤ 2.328). By multivariate logistic regression analysis, retraction phenomenon was the strongest independent predictor for the Luminal-A subtype (OR = 9.063, P<0.001) when present and for the Triple-Negative subtype (OR = 4.875, P<0.001) when absent.ConclusionsABVS imaging features, especially retraction phenomenon, have a strong correlation with the molecular subtypes, expanding the scope of ultrasound in identifying breast cancer subtypes with confidence. 相似文献
997.
Diane Dufour-Rainfray Patrick Vourc’h Anne-Marie Le Guisquet Lucette Garreau David Ternant Sylvie Bodard Emilie Jaumain Zuhal Gulhan Catherine Belzung Christian R. Andres Sylvie Chalon Denis Guilloteau 《Neuroscience letters》2010
In order to explore whether some aspects of the autistic phenotype could be related to impairment of the serotonergic system, we chose an animal model which mimics a potential cause of autism, i.e. rats exposed to valproate (VPA) on the 9th embryonic day (E9). Previous studies have suggested that VPA exposure in rats at E9 caused a dramatic shift in the distribution of serotonergic neurons on postnatal day 50 (PND50). Behavioral studies have also been performed but on rats that were exposed to VPA later (E12.5). Our aim was to test whether VPA exposure at E9 induces comparable behavioral impairments than at E12.5 and causes serotonergic impairments which could be related to behavioral modifications. The results showed significant behavioral impairments such as a lower tendency to initiate social interactions and hyperlocomotor activity in juvenile male rats. The serotonin levels of these animals at PND50 were decreased (−46%) in the hippocampus, a structure involved in social behavior. This study suggests that VPA could have a direct or indirect action on the serotonergic system as early as the progenitor cell stage. Early embryonic exposure to VPA in rats provides a good model for several specific aspects of autism and should help to continue to explore pathophysiological hypotheses. 相似文献
998.
Can Lai Xi Qun Wang Long Lin De Chun Gao Hong Xi Zhang Yi Ying Zhang Yin Bao Zhou 《Korean journal of radiology》2010,11(4):480-484
We report here a case of pentastomiasis infection in a 3-year-old girl who had high fever, abdominal pain, abdominal tension and anemia. Ultrasound scanning of the abdomen revealed disseminated hyperechoic nodules in the liver and a small amount of ascites. Abdominal MRI showed marked hepatomegaly with disseminated miliary nodules of high signal intensity throughout the hepatic parenchyma on T2-weighted images; retroperitoneal lymphadenopathy and disseminated miliary nodules on the peritoneum were also noted. Chest CT showed scattered small hyperdense nodules on both sides of the lungs. The laparoscopy demonstrated diffuse white nodules on the liver surface and the peritoneum. After the small intestinal wall and peritoneal biopsy, histological examination revealed parenchymal tubercles containing several larvae of pentastomids and a large amount of inflammatory cell infiltration around them. The pathological diagnosis was parasitic granuloma from pentastomiasis infection. 相似文献
999.
ObjectiveThe aim of this research was to check the effect of the prenatally administered β-hydroxy β-methylbutyrate (HMB) on the development of enamel surface of the spiny mice offspring.DesignThe spiny mice dams were randomly assigned into three groups: control group (not supplemented with HMB) and two experimental groups in which powdered HMB was given at the daily dosage of 0.2 g/kg of body weight (group I) and 0.02 g/kg of body weight (group II) during the last period of gestation. Newborn pups were euthanized by CO2 inhalation. The morphology of incisor teeth was analysed using atomic force microscopy (AFM) in semi-contact mode in the height, magnitude and phase domains. Height images became a basis for determination of surface roughness parameters.ResultsConducted study indicated that maternal HMB administration markedly influences enamel development. Enamel of offspring’s teeth in both experimental groups was characterized by significantly smaller values of indices describing surface roughness and profile. HMB supplementation influenced the calculated parameters regardless of the diet type and offspring sex, however higher dose of HMB caused stronger changes in enamel surface’s physical properties and could be observed in higher intensity in the male group.ConclusionsHMB administration caused reduction in the irregularities of enamel surface, thereby possibly reducing the probability of bacteria adhesion and caries development. These observations may serve to improve nutrition and supplementation of animals and could be a lead for further research. 相似文献
1000.